In recent years, known is a telematics system of using a communication line of a mobile communication terminal (“mobile terminal”) such as a smartphone and connecting an in-vehicle terminal of a car navigation or the like and a data center, and providing various car navigation-related services through such communication line.
Moreover, if some kind of failure occurs in the in-vehicle terminal or the mobile terminal, the log data stored in the in-vehicle terminal or the mobile terminal is collected by the data center, and the data center analyzes the failure that occurred in the in-vehicle terminal or the mobile terminal.
For example, in PTL 1, a web server that received a request from a client generates a transaction ID (Identification) for identifying the series of processes, routes the generated transaction ID among a plurality of servers and outputs a log including the transaction ID, and the person in charge who received a complaint from the client terminal to the effect that the screen display is slow searches for a log corresponding to the condition of “all processing times are a given length of time or longer”, narrows down the logs by using the transaction ID, and thereby determines which process took time.